Display device

ABSTRACT

A display device may include a main flexible printed circuit including a first alignment mark and electrically connected to a first panel; and a touch flexible printed circuit including a second alignment mark and electrically connected to a second panel that is perpendicular to the first panel, wherein the main flexible printed circuit is electrically connected to the touch flexible printed circuit through a pad region, and the touch flexible printed circuit includes a first overcoat region disposed between the first alignment mark and the second alignment mark.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This is a continuation application of U.S. Pat. Application No.17/231,507, filed Apr. 15, 2021 (now pending), the disclosure of whichis incorporated herein by reference in its entirety. U.S. Pat.Application No. 17/231,507 claims priority to and the benefit of KoreanPatent Application No. 10-2020-0110163 filed in the Korean IntellectualProperty Office (KIPO) on Aug. 31, 2020, the entire contents of whichare incorporated herein by reference.

BACKGROUND 1. Technical Field

The described technology relates generally to a display device.

2. Description of the Related Art

Flat panel displays (FPD) such as an organic light emitting diodedisplay (OLED), a liquid crystal display (LCD), or an electrophoreticdisplay (EPD) include a field generating electrode and anelectro-optical active layer. As the electro-optical active layer, theorganic light emitting device includes an organic emission layer, theliquid crystal display includes a liquid crystal layer, and theelectrophoretic display includes charged particles. The field generatingelectrode may be electrically connected to a switching element such as athin film transistor and may receive a data signal, and theelectro-optical active layer displays images by converting the datasignal into an optical signal.

The display device may include a touch sensing function for allowing aninteraction with a user in addition to a function for displaying animage. The touch sensing function is used by the display device to findtouch information such as whether an object approaches or touches ascreen and a touch location thereof by sensing changes in pressure,charges, light, and the like which are applied to the screen, when theuser writes text or draws figures by approaching or touching the screenusing a finger or a touch pen. The display device may receive an imagesignal based on such touch information.

The above information disclosed in this Background section is only forenhancement of understanding of the background of the describedtechnology, and therefore it may contain information that does not formthe prior art that is already known in this country to a person ofordinary skill in the art.

SUMMARY

The described technology has been made in an effort to provide a displaydevice with an overcoat forming structure (or a coverlay on structure)for preventing a touch flexible printed circuit from being damaged in aprocess for compressing a main flexible printed circuit (MFPC) and atouch flexible printed circuit (TFPC) and bonding them.

The described technology has been made in another effort to provide adisplay device for preventing interference between an alignment mark andan opening in an overcoat forming structure.

An embodiment provides a display device including a main flexibleprinted circuit including a first alignment mark and electricallyconnected to a first panel; and a touch flexible printed circuitincluding a second alignment mark and electrically connected to a secondpanel that is perpendicular to the first panel, wherein the mainflexible printed circuit may be electrically connected to the touchflexible printed circuit through a pad region, and the touch flexibleprinted circuit may include a first overcoat region disposed between thefirst alignment mark and the second alignment mark.

The first overcoat region may be disposed between the second alignmentmark and a first edge of the touch flexible printed circuit.

The touch flexible printed circuit may include a first opening thatpenetrates through the touch flexible printed circuit on an oppositeside to the first overcoat region with respect to the second alignmentmark; and a second overcoat region disposed between the second alignmentmark and the first opening.

A width of the first overcoat region may be greater than a width of thesecond overcoat region.

A width of the first overcoat region may be equal to or less than awidth of the second overcoat region.

The first overcoat region and the second overcoat region may be disposedbelow the pad region.

The main flexible printed circuit may include a third alignment mark,and the touch flexible printed circuit may include a fourth alignmentmark, and a third overcoat region disposed between the third alignmentmark and the fourth alignment mark.

The third overcoat region may be disposed between the fourth alignmentmark and a second edge of the touch flexible printed circuit.

The touch flexible printed circuit may include a second opening thatpenetrates through the touch flexible printed circuit on an oppositeside to the third overcoat region with respect to the fourth alignmentmark; and a fourth overcoat region disposed between the fourth alignmentmark and the second opening.

A width of the third overcoat region may be greater than a width of thefourth overcoat region.

A width of the third overcoat region may be equal to or less than awidth of the fourth overcoat region.

The third overcoat region and the fourth overcoat region may be disposedbelow the pad region.

Another embodiment provides a base film; a first alignment mark and asecond alignment mark disposed on the base film for arrangement with amain flexible printed circuit; a first overcoat region provided on thebase film and disposed between the first alignment mark and a first edgeof the base film; and a second overcoat region disposed between a secondedge facing the first edge and the second alignment mark.

The display device may further include a first opening that penetratesthrough the base film on an opposite side to the first overcoat regionwith respect to the first alignment mark; and a third overcoat regiondisposed between the first alignment mark and the first opening.

A width of the first overcoat region may be greater than a width of thethird overcoat region.

A width of the first overcoat region may be equal to or less than awidth of the third overcoat region.

The display device may further include a second opening that penetratesthrough the base film on an opposite side to the second overcoat regionwith respect to the second alignment mark; and a fourth overcoat regiondisposed between the second alignment mark and the second opening.

A width of the second overcoat region may be greater than a width of thefourth overcoat region.

A width of the second overcoat region may be equal to or less than awidth of the fourth overcoat region.

The base film may be electrically connected to the main flexible printedcircuit through a pad region.

According to the embodiments, the display device with an overcoatforming structure in which the overcoat is formed between the edge ofthe touch flexible printed circuit and the alignment mark is provided,so regarding the process for compressing the main flexible printedcircuit and the touch flexible printed circuit and the process formanufacturing a display device, damage such as tearing or breaking ofthe touch flexible printed circuit because of the stress may beprevented and the inferiority rate may be substantially reduced.

According to the embodiments, the sufficient margin between thealignment mark and the opening is secured when the overcoat formingstructure is applied, so the accuracy of the bonding process may behighly maintained by preventing the interference between the alignmentmark and the opening.

BRIEF DESCRIPTION OF THE DRAWINGS

An additional appreciation according to the embodiments of thedisclosure will become more apparent by describing in detail theembodiments thereof with reference to the accompanying drawings,wherein:

FIG. 1 schematically illustrates a plan view of a display deviceaccording to an embodiment.

FIG. 2 schematically illustrates a side view of a display devicedescribed with reference to FIG. 1 .

FIG. 3 schematically illustrates a partial enlarged view of a front sideof a bonded region of a display device to which a structure for formingan overcoat is applied according to an embodiment.

FIG. 4 schematically illustrates a partial enlarged view of a rear sideof a bonded region of a display device to which a structure for formingan overcoat is applied according to an embodiment.

FIG. 5 schematically illustrates a cross-sectional view of a touchflexible printed circuit taken along line A-A′ of FIG. 3 .

FIG. 6 schematically illustrates a partial enlarged view of a front sideof a bonded region of a display device to which a structure for formingan overcoat is applied according to an embodiment.

FIG. 7 schematically illustrates a cross-sectional view of a touchflexible printed circuit taken along line B-B′ of FIG. 6 .

FIG. 8 schematically illustrates a partial enlarged view of a front sideof a bonded region of a display device to which a structure for formingan overcoat is applied according to an embodiment.

FIG. 9 schematically illustrates a cross-sectional view of a touchflexible printed circuit taken along line C-C′ of FIG. 8 .

DETAILED DESCRIPTION OF THE EMBODIMENTS

The disclosure will be described more fully hereinafter with referenceto the accompanying drawings, in which embodiments of the disclosure areillustrated. As those skilled in the art would realize, the describedembodiments may be modified in various different ways, all withoutdeparting from the spirit or scope of the disclosure.

Parts that are irrelevant to the description may be omitted to clearlydescribe the disclosure, and the same elements will be denoted by thesame reference numerals throughout the specification.

The size and thickness of each configuration illustrated in the drawingsare arbitrarily illustrated for better understanding and ease ofdescription, but the disclosure is not limited thereto. In the drawings,the thickness of layers, films, panels, regions, etc., may beexaggerated for clarity. The thicknesses of some layers and areas areexaggerated for convenience of explanation.

It will be understood that when an element such as a layer, film,region, or substrate is referred to as being “on” another element, itcan be directly on the another element or intervening elements may alsobe present. In contrast, when an element is referred to as being“directly on” another element, there are no intervening elementspresent. The word “on” or “above” means positioned on or below theobject portion and does not necessarily mean positioned on the upperside of the object portion based on a gravitational direction.

Unless explicitly described to the contrary, the word “comprise,”“include,” and variations such as “comprising” or “including” will beunderstood to imply the inclusion of stated elements but not theexclusion of any other elements.

The phrase “in a plan view” means viewing an object portion from thetop, and the phrase “in a cross-sectional view” means viewing across-section of the object portion vertically cut from the side.

In the specification and the claims, the phrase “at least one of” isintended to include the meaning of “at least one selected from the groupof′ for the purpose of its meaning and interpretation. For example, “atleast one of A and B” may be understood to mean “A, B, or A and B.”

Unless otherwise defined or implied herein, all terms (includingtechnical and scientific terms) used herein have the same meaning ascommonly understood by those skilled in the art to which this disclosurepertains. It will be further understood that terms, such as thosedefined in commonly used dictionaries, should be interpreted as having ameaning that is consistent with their meaning in the context of therelevant art and the disclosure, and should not be interpreted in anideal or excessively formal sense unless clearly so defined herein.

FIG. 1 illustrates a schematic plan view of a display device accordingto an embodiment, and FIG. 2 illustrates a schematic side view of adisplay device described with reference to FIG. 1 .

Referring to FIGS. 1 and 2 , a display device 1 may include a lowersubstrate 100, a displaying layer 200, an upper substrate 300, and atouch sensing layer 400. The display device 1 may include a mainflexible printed circuit 600 connected to the displaying layer 200 and atouch flexible printed circuit 700 connected to the touch sensing layer400. The display device 1 may include a displaying driving chip 500 anda touch driving chip 550.

The display device 1 may include a display area DA for displaying imagesand a peripheral area PA positioned around the display area DA in FIG. 1, and the display area DA may be defined in the displaying layer 200illustrated in FIG. 2 .

Pixels may be disposed in the display area DA. The respective pixelsinclude a thin film transistor (TFT) and a capacitor and may include anelectro-optical active layer. Displaying signal lines (not shown) fortransmitting driving signals may be positioned in the display area DA,and the displaying signal lines may include a gate line for transmittinga gate signal and a data line for transmitting a data signal. Thedisplaying signal lines may extend to the peripheral area PA and mayform a pad portion (not shown) on the lower substrate 100. Thedisplaying layer 200 may include pixels and displaying signal lineselectrically connected to the pixels and transmitting signals, and theymay be formed on the lower substrate 100.

The touch sensing layer 400 disposed in the touch active area (TA) maybe formed on the upper substrate 300. The touch sensing layer 400 mayinclude a touch electrode (not shown) and a touch signal line (notshown) for transmitting and/or receiving signals to/from the touchelectrode. The touch signal line may extend to form a pad portion (notshown) on the upper substrate 300.

The touch active area TA may be the entire display area DA, or mayinclude part of the peripheral area PA. Further, part of the displayarea DA may be the touch active area TA. The touch sensing layer 400 maysense touches in various ways. For example, a touch sensor may beclassified into various types such as a resistive type, a capacitivetype, an electro-magnetic type (EM), or an optical type.

The displaying driving chip 500 may include driving devices including adata driver for applying a data voltage to the data line, a gate driverfor applying a gate-on voltage to the gate line, and a signal controllerfor controlling operations of the data driver and the gate driver. Thedisplaying driving chip 500 may be positioned on the substrate, forexample, in the peripheral area (PA) of the lower substrate 100. In someembodiments, the displaying driving chip 500 may be positioned on themain flexible printed circuit 600 or a printed circuit board (PCB) (notshown).

The touch driving chip 550 may transmit a sensing input signal to thetouch sensing layer 400. The touch driving chip 550 may generate touchinformation such as a touched state and a touched position by processinga sensing output signal from the touch sensing layer 400. The touchdriving chip 550 may be positioned on the touch flexible printed circuit700. In some embodiments, the touch driving chip 550 may be positionedin the peripheral area PA of the substrate, for example, the uppersubstrate 300, or may be positioned on an additional printed circuitboard (PCB) (not shown).

A signal for controlling the displaying driving chip 500 or thedisplaying layer 200 may be applied through the main flexible printedcircuit 600. The main flexible printed circuit 600 may include a firstconnector attached to an attachment region (not shown) of the lowersubstrate 100 and connecting the main flexible printed circuit 600 tothe displaying layer 200 formed on the lower substrate 100. In thisinstance, the connection to the displaying layer 200 must be understoodto include a connection through the displaying driving chip 500positioned on the lower substrate 100. A film such as an anisotropicconductive film (ACF) may be used, for ease of adhesion, between thefirst connector and the attachment region of the lower substrate 100.The main flexible printed circuit 600 may include a second connector fora connection to the touch flexible printed circuit 700, and it mayinclude an input portion for receiving a signal from the outside, and abody portion on which various circuit elements are disposed.

Signals may be transmitted to or received from the touch sensing layer400 through the touch flexible printed circuit 700. The touch flexibleprinted circuit 700 may include a body portion 710, a connector 720, aterminal portion 730, and a bonded region 740.

The connector 720 may be attached to an attachment region (not shown) ofthe upper substrate 300 to electrically connect the touch flexibleprinted circuit 700 to the touch sensing layer 400 formed on the uppersubstrate 300. A film such as an anisotropic conductive film may bepositioned between the connector 720 and the attachment region of theupper substrate 300. The touch driving chip 550 may be mounted on thebody portion 710, and a signal from the touch driving chip 550 and asignal from the touch sensing layer 400 may be transmitted through theconnector 720.

The terminal portion 730 may extend from an end of the body portion 710facing the connector 720. The terminal portion 730 may substantially berectangular and may be integral with the body portion 710. The terminalportion 730 may be flat in case that no force is applied thereto, or aportion thereof may be bent in a U shape. In the latter case, the Ushape may be flattened in case that a force is applied thereto, and itmay be restored to the U shape in case that the force is removed. Apredetermined portion of the terminal portion 730 may be thinner thanother portions thereof, and it may be more flexible than them. Theterminal portion 730 may be shorter in case that it is bent than it isflattened.

The bonded region 740 may be formed at the end of the terminal portion730, and it may be connected to a second connector of the main flexibleprinted circuit 600. By this, the touch flexible printed circuit 700 mayreceive an external signal input through an input portion of the mainflexible printed circuit 600 and/or a signal generated or processed by acircuit element of the main flexible printed circuit 600. In someembodiments, the touch flexible printed circuit 700 may be connected tothe main flexible printed circuit 600 through bonding of the anisotropicconductive film in the bonded region 740.

A cushion layer (not shown) for protecting the lower substrate 100 maybe formed on a rear side of the lower substrate 100. A window (notshown) for protecting the lower substrate 100, the displaying layer 200,the upper substrate 300, and the touch sensing layer 400 may be formedon the touch sensing layer 400. In case that the display device is anorganic light emitting device, the upper substrate 300 may be anencapsulation substrate for preventing moisture and/or oxygen frompermeating from the outside.

To manufacture the display device, a manufacturing process such as achip on glass (COG) process, a flexible printed circuit (FPC) on glass(FOG) process, a chip on flex (COF) process, a touch film on glass(TFOG) process, an outer lead bonding (OLB) process, or an FPC on film(FOF) process may be performed. Particularly, a compressing and bondingprocess for configuring a circuit by compressing the touch flexibleprinted circuit 700 on the main flexible printed circuit 600 at a hightemperature and a high pressure by using the anisotropic conductive filmmay be performed to bond the main flexible printed circuit 600 to thetouch flexible printed circuit 700.

FIG. 3 schematically illustrates a partial enlarged view of a front sideof a bonded region of a display device having a structure for forming anovercoat according to an embodiment, and FIG. 4 schematicallyillustrates a partial enlarged view of a rear side of a bonded region ofa display device having a structure for forming an overcoat according toan embodiment, and illustrates a bonded region 740.

Referring to FIGS. 3 and 4 , a connector 640 may be a region included inthe main flexible printed circuit 600, and it may be defined as a regionincluding a pad region 649 in which terminals 6490 are positioned for aconnection to the touch flexible printed circuit 700. The bonded region740 may represent a state in which the connector 640 of the mainflexible printed circuit 600 and the terminal portion 730 of the touchflexible printed circuit 700 are disposed to overlap each other for acompressing and bonding process.

Referring to FIGS. 3 and 4 , to perform a process for compressing andbonding the main flexible printed circuit 600 and the touch flexibleprinted circuit 700, it is needed to arrange the main flexible printedcircuit 600 and the touch flexible printed circuit 700. In case that themain flexible printed circuit 600 and the touch flexible printed circuit700 are correctly arranged and the touch flexible printed circuit 700 iscompressed on the main flexible printed circuit 600 at a hightemperature and a high pressure by using an anisotropic conductivelayer, the main flexible printed circuit 600 and the touch flexibleprinted circuit 700 may be electrically connected to each other throughthe pad region 649, for example, the terminals 6490 positioned in thepad region 649. In the embodiment, the main flexible printed circuit 600may be a circuit electrically connected to a first panel and may includealignment marks 641, 642, 643, and 644. Here, the first panel maycorrespond to the lower substrate 100 and the displaying layer 200 inFIGS. 1 and 2 .

The touch flexible printed circuit 700 may be a circuit electricallyconnected to the second panel perpendicularly disposed on the firstpanel and may include alignment marks 741 and 743. Here, the secondpanel may correspond to the upper substrate 300 and the touch sensinglayer 400 in FIGS. 1 and 2 .

The alignment mark 641 formed on a front side of the connector 640 ofthe main flexible printed circuit 600 may make a pair with the alignmentmark 741 formed on the terminal portion 730 of the touch flexibleprinted circuit 700 to become an index for confirming whether the mainflexible printed circuit 600 and the touch flexible printed circuit 700are arranged or aligned. Likewise, the alignment mark 643 formed on afront side of the connector 640 of the main flexible printed circuit 600may make a pair with the alignment mark 743 formed on the terminalportion 730 of the touch flexible printed circuit 700 to become an indexfor confirming whether the main flexible printed circuit 600 and thetouch flexible printed circuit 700 are arranged or aligned.

In the embodiment, the touch flexible printed circuit 700 may include anovercoat region (or coverlay region) C1 formed between the alignmentmark 641 and the alignment mark 741. Here, the overcoat region C1 may bea part of the terminal portion 730 of the touch flexible printed circuit700 for covering or overlapping the connector 640 of the main flexibleprinted circuit 600.

As the overcoat region C1 is formed between the alignment mark 641 andthe alignment mark 741, in the process for manufacturing a displaydevice in addition to the process for compressing the main flexibleprinted circuit 600 and the touch flexible printed circuit 700, forexample, in case that a stress is applied toward the alignment mark 741,breakage of the touch flexible printed circuit 700 such as being torn ordamaged may be prevented.

Likewise, the touch flexible printed circuit 700 may include an overcoatregion C2 formed between the alignment mark 643 and the alignment mark743, the overcoat region C2 may be a part of the terminal portion 730 ofthe touch flexible printed circuit 700 for covering the connector 640 ofthe main flexible printed circuit 600, and the overcoat region C2 mayease the stress generated toward the alignment mark 743.

In the embodiment, the overcoat regions C1 and C2 may be respectivelyformed between the alignment marks 741 and 743 and the edges E1 and E2of the touch flexible printed circuit 700. Accordingly, as a bufferregion formed as a part of the terminal portion 730 of the touchflexible printed circuit 700 in an external direction from the alignmentmarks 741 and 743 is obtained, the touch flexible printed circuit 700may be firmly maintained in case that the stress is applied toward thealignment marks 741 and 743.

The structure including the overcoat regions C1 and C2 as describedabove may also be referred to as an overcoat forming structure in thespecification. By applying the overcoat forming structure to the displaydevice, the fraction defective of the display device may besubstantially reduced by preventing damage to the touch flexible printedcircuit 700 that may occur during the manufacturing process.

In the embodiment, the overcoat regions C1 and C2 may be formed belowthe pad region 649, but the disclosure is not limited thereto, andforming positions of the overcoat regions C1 and C2 may vary accordingto detailed implementation purposes.

The touch flexible printed circuit 700 may further include an opening745 penetrating through the touch flexible printed circuit 700 on anopposite side to the overcoat region C1 with respect to the alignmentmark 741, and an opening 747 penetrating through the touch flexibleprinted circuit 700 on an opposite side to the overcoat region C2 withrespect to the alignment mark 743. The openings 745 and 747 may beformed in the positions respectively corresponding to openings 647 and645 penetrating through the main flexible printed circuit 600. Theopenings 645, 647, 745, and 747 may be used to fix the main flexibleprinted circuit 600 or the touch flexible printed circuit 700 to otherparts or may be used for other purposes. A cross-sectional configurationof the openings 645 and 647 are described with reference to FIG. 5 , andthe cross-sectional configuration of the openings 745 and 747 may beidentical or substantially identical to that of the openings 645 and647.

FIG. 5 illustrates a schematic cross-sectional view of a touch flexibleprinted circuit 700 taken along line A-A′ of FIG. 3 .

Referring to FIG. 5 , the touch flexible printed circuit 700 may includea base film 701, alignment marks 741 and 743, and overcoat regions C1and C2. Here, the base film 701 may allow the terminal positioned on thebase film 701 to overlap the pad region 649and thereby form anelectrical connection with the main flexible printed circuit 600, andthe alignment marks 741 and 743 may be formed on the base film 701 forarrangement with the main flexible printed circuit 600. The overcoatregion C1 may be formed on the base film 701 between the alignment mark741 and the edge E1 of the base film 701, and the overcoat region C2 maybe formed between the edge E2 facing the edge E1 and the alignment mark743.

In the embodiment, the overcoat region C1 and the overcoat region C2 mayhave the same or substantially the same width, but the disclosure is notlimited thereto, and the overcoat region C1 and the overcoat region C2may have different widths depending on detailed implementation purposes.

In this embodiment, the base film 701 is illustrated as being formedbetween the opening 745 and the opening 747, but the disclosure is notlimited thereto, and another film or overcoat may be additionally formedon the base film 701 between the opening 745 and the opening 747according to detailed implementation purposes.

FIG. 6 schematically illustrates a partial enlarged view of a front sideof a bonded region of a display device to which a structure for formingan overcoat is applied according to an embodiment, and illustrates abonded region 740A.

Referring to FIG. 6 , the touch flexible printed circuit 700 may includean overcoat region C1 formed between the alignment mark 641 and thealignment mark 741. Here, the overcoat region C1 may be a part of theterminal portion 730 of the touch flexible printed circuit 700 forcovering the connector 640 of the main flexible printed circuit 600. Thetouch flexible printed circuit 700 may further include an overcoatregion C3 formed between the alignment mark 741 and the opening 745, andthe overcoat region C3 may be a part of the terminal portion 730 of thetouch flexible printed circuit 700 for covering the connector 640 of themain flexible printed circuit 600.

Likewise, the touch flexible printed circuit 700 may include an overcoatregion C2 formed between the alignment mark 643 and the alignment mark743. Here, the overcoat region C2 may be a part of the terminal portion730 of the touch flexible printed circuit 700 for covering the connector640 of the main flexible printed circuit 600. The touch flexible printedcircuit 700 may further include an overcoat region C4 formed between thealignment mark 743 and the opening 747, and the overcoat region C4 maybe a part of the terminal portion 730 of the touch flexible printedcircuit 700 for covering the connector 640 of the main flexible printedcircuit 600.

The overcoat regions C1 and C3 may ease stress generated toward thealignment mark 741, and the overcoat regions C2 and C4 may ease stressgenerated toward the alignment mark 743.

By applying the overcoat forming structure including the overcoatregions C1, C2, C3, and C4 to the display device, the fraction defectiveof the display device may be substantially reduced by preventing damageto the touch flexible printed circuit 700 that may occur during themanufacturing process.

In the embodiment, the overcoat regions C1, C2, C3, and C4 may be formedbelow the pad region 649, but the disclosure is not limited thereto, andthe forming positions of the overcoat regions C1, C2, C3, and C4 mayvary depending on the detailed implementation purposes.

FIG. 7 illustrates a schematic cross-sectional view of a touch flexibleprinted circuit 700 taken along line B-B′ of FIG. 6 .

Referring to FIG. 7 , the touch flexible printed circuit 700 may includea base film 701, alignment marks 741 and 743, and overcoat regions C1,C2, C3, and C4. Here, the alignment marks 741 and 743 may be formed onthe base film 701 for arrangement with the main flexible printed circuit600. The overcoat region C1 may be formed on the base film 701 betweenthe alignment mark 741 and the edge E1 of the base film 701, and theovercoat region C2 may be formed between the edge E2 facing the edge E1and the alignment mark 743. The overcoat region C3 may be formed betweenthe alignment mark 741 and the opening 745, and the overcoat region C4may be formed between the alignment mark 743 and the opening 747.

In the embodiment, a width W1 of the overcoat region C1 may be greaterthan a width W3 of the overcoat region C3. A width W2 of the overcoatregion C2 may be greater than a width W4 of the overcoat region C4.

In the embodiment, the overcoat region C1 and the overcoat region C2 maygenerally have the same or substantially the same width, but thedisclosure is not limited thereto, and the overcoat region C1 and theovercoat region C2 may have different widths depending on detailedimplementation purposes.

Likewise, the overcoat region C3 and the overcoat region C4 maygenerally have the same or substantially the same width, but thedisclosure is not limited thereto, and the overcoat region C3 and theovercoat region C4 may have different widths depending on detailedimplementation purposes.

In the embodiment, the base film 701 is illustrated as being formedbetween the opening 745 and the opening 747, but the disclosure is notlimited thereto, and another film or overcoat may be additionally formedon the base film 701 between the opening 745 and the opening 747.

FIG. 8 schematically illustrates a partial enlarged view of a front sideof a bonded region of a display device having a structure for forming anovercoat according to an embodiment, and illustrates a bonded region740B, and FIG. 9 schematically illustrates a cross-sectional view of atouch flexible printed circuit taken along line C-C′ of FIG. 8 .

As described with reference to FIG. 6 , the touch flexible printedcircuit 700 may include an overcoat region C1 positioned between thealignment mark 641 and the alignment mark 741, an overcoat region C2positioned between the alignment mark 643 and the alignment mark 743, anovercoat region C3 positioned between the alignment mark 741 and theopening 745, and an overcoat region C4 positioned between the alignmentmark 743 and the opening 747.

The overcoat regions C1 and C3 may ease stress generated toward thealignment mark 741, and the overcoat regions C2 and C4 may ease stressgenerated toward the alignment mark 743.

As described with reference to FIG. 7 , the touch flexible printedcircuit 700 may include a base film 701, alignment marks 741 and 743,and overcoat regions C1, C2, C3, and C4.

In the embodiment, a width W1 of the overcoat region C1 may be equal toor less than a width W3 of the overcoat region C3. A width W2 of theovercoat region C2 may be equal to or less than a width W4 of theovercoat region C4.

In the embodiment, the overcoat region C1 and the overcoat region C2 maygenerally have the same or substantially the same width, but thedisclosure is not limited thereto, and the overcoat region C1 and theovercoat region C2 may have different widths depending on detailedimplementation purposes.

Likewise, the overcoat region C3 and the overcoat region C4 maygenerally have the same or substantially the same width, but thedisclosure is not limited thereto, and the overcoat region C3 and theovercoat region C4 may have different widths depending on detailedimplementation purposes.

In the embodiment, the base film 701 is illustrated as being formedbetween the opening 745 and the opening 747, but the disclosure is notlimited thereto, and another film or overcoat may be additionally formedon the base film 701 between the opening 745 and the opening 747.

According to the embodiments described with reference to FIGS. 6 and 9 ,in case that the overcoat forming structure is applied to the displaydevice, a sufficient margin between the alignment marks 741 and 743 andthe openings 745 and 747 may be obtained, and thus interference betweenthe alignment marks 741 and 743 and the openings 745 and 747 may beprevented so that high accuracy of the bonding process may bemaintained.

According to the above-described embodiments, the display device havingan overcoat forming structure in which the overcoat is formed betweenthe edge of the touch flexible printed circuit and the alignmentmark,may be provided. Therefore, regarding the process for compressingthe main flexible printed circuit and the touch flexible printed circuitand the process for manufacturing a display device, damage such astearing or breaking of the touch flexible printed circuit because of thestress may be prevented, and the fraction defective may be substantiallyreduced.

According to the embodiments, a sufficient margin between the alignmentmark and the opening may be secured in case that the overcoat formingstructure is applied to the display device, so that high accuracy of thebonding process may be maintained by preventing the interference betweenthe alignment mark and the opening.

While this disclosure has been described in connection with what ispresently considered to be practical embodiments, it is to be understoodthat the disclosure is not limited to the disclosed embodiments, but, onthe contrary, is intended to cover various modifications and equivalentarrangements included within the spirit and scope of the appendedclaims.

What is claimed is:
 1. A display device comprising: a first flexibleprinted circuit including a first alignment mark and a first opening,the first flexible printed circuit electrically connected to adisplaying layer; and a second flexible printed circuit including asecond alignment mark and a second opening, the second flexible printedcircuit electrically connected to a touch sensing layer that overlapsthe displaying layer, wherein the first flexible printed circuit iselectrically connected to the second flexible printed circuit through apad region, and the first alignment mark, the second alignment mark andthe second opening are disposed on a first straight line.
 2. The displaydevice of claim 1, wherein the first alignment mark comprises a firstsub-alignment mark and a second sub-alignment mark, and the secondalignment mark comprises a third sub-alignment mark and a fourthsub-alignment mark.
 3. The display device of claim 2, wherein the firstsub-alignment mark, the third sub-alignment mark, the fourthsub-alignment mark and the second sub-alignment mark are arranged inorder in a plan view.
 4. The display device of claim 2, wherein thethird sub-alignment mark and the fourth sub-alignment mark are disposedbetween the first sub-alignment mark and the second sub-alignment mark.5. The display device of claim 4, wherein the third sub-alignment markis disposed between the first sub-alignment mark and the fourthsub-alignment mark.
 6. The display device of claim 4, wherein thefourth-sub alignment mark is disposed between the third sub-alignmentmark and the second sub-alignment mark.
 7. The display device of claim2, wherein the first sub-alignment mark, the third sub-alignment mark,the fourth sub-alignment mark and the second sub-alignment mark aredisposed on the first straight line.
 8. The display device of claim 2,wherein the first opening comprises a first sub-opening and a secondsub-opening, and the second opening comprises a third sub-opening and afourth sub-opening.
 9. The display device of claim 8, wherein the firstsub-opening and the third sub-opening overlap each other, and the secondsub-opening and the fourth sub-opening overlap each other.
 10. Thedisplay device of claim 8, wherein the first sub-opening and the thirdsub-opening are disposed between the third sub-alignment mark and thefourth sub-alignment mark.
 11. The display device of claim 8, whereinthe second sub-opening and the fourth sub-opening are disposed betweenthe third sub-alignment mark and the fourth sub-alignment mark.
 12. Thedisplay device of claim 8, wherein the first sub-alignment mark, thethird sub-alignment mark and the third sub-opening are disposed on thefirst straight line.
 13. The display device of claim 8, wherein thesecond sub-alignment mark, the fourth sub-alignment mark and the fourthsub-opening are disposed on the first straight line.
 14. The displaydevice of claim 8, wherein the first sub-alignment mark, the thirdsub-alignment mark, the third sub-opening, the fourth sub-opening, thefourth sub-alignment mark and the second sub-alignment mark are disposedon the first straight line.
 15. The display device of claim 8, whereinthe second flexible printed circuit includes: a first overcoat regiondisposed between the first sub-alignment mark and the thirdsub-alignment mark; and a second overcoat region disposed between thesecond sub-alignment mark and the fourth sub-alignment mark.
 16. Thedisplay device of claim 15, wherein the second flexible printed circuitfurther includes: a third overcoat region disposed between the thirdsub-alignment mark and the third opening; and a fourth overcoat regiondisposed between the fourth sub-alignment mark and the fourth opening.17. The display device of claim 16, wherein a width of the thirdovercoat region is greater than a width of the first overcoat region.18. The display device of claim 16, wherein a width of the fourthovercoat region is greater than a width of the second overcoat region.19. The display device of claim 16, wherein the first straight linepasses through the first overcoat region.
 20. The display device ofclaim 16, wherein the first flexible printed circuit further comprises aplurality of pads, and each of the third sub-alignment mark and thefourth sub-alignment mark overlaps a part of a plurality of pads.